1 /*
2  * drivers/net/ethernet/mellanox/mlxsw/spectrum_cnt.c
3  * Copyright (c) 2017 Mellanox Technologies. All rights reserved.
4  * Copyright (c) 2017 Arkadi Sharshevsky <arkadis@mellanox.com>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the names of the copyright holders nor the names of its
15  *    contributors may be used to endorse or promote products derived from
16  *    this software without specific prior written permission.
17  *
18  * Alternatively, this software may be distributed under the terms of the
19  * GNU General Public License ("GPL") version 2 as published by the Free
20  * Software Foundation.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <linux/kernel.h>
36 #include <linux/bitops.h>
37 
38 #include "spectrum_cnt.h"
39 
40 #define MLXSW_SP_COUNTER_POOL_BANK_SIZE 4096
41 
42 struct mlxsw_sp_counter_sub_pool {
43 	unsigned int base_index;
44 	unsigned int size;
45 	unsigned int entry_size;
46 	unsigned int bank_count;
47 };
48 
49 struct mlxsw_sp_counter_pool {
50 	unsigned int pool_size;
51 	unsigned long *usage; /* Usage bitmap */
52 	struct mlxsw_sp_counter_sub_pool *sub_pools;
53 };
54 
55 static struct mlxsw_sp_counter_sub_pool mlxsw_sp_counter_sub_pools[] = {
56 	[MLXSW_SP_COUNTER_SUB_POOL_FLOW] = {
57 		.bank_count = 6,
58 	},
59 	[MLXSW_SP_COUNTER_SUB_POOL_RIF] = {
60 		.bank_count = 2,
61 	}
62 };
63 
64 static int mlxsw_sp_counter_pool_validate(struct mlxsw_sp *mlxsw_sp)
65 {
66 	unsigned int total_bank_config = 0;
67 	unsigned int pool_size;
68 	int i;
69 
70 	pool_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, COUNTER_POOL_SIZE);
71 	/* Check config is valid, no bank over subscription */
72 	for (i = 0; i < ARRAY_SIZE(mlxsw_sp_counter_sub_pools); i++)
73 		total_bank_config += mlxsw_sp_counter_sub_pools[i].bank_count;
74 	if (total_bank_config > pool_size / MLXSW_SP_COUNTER_POOL_BANK_SIZE + 1)
75 		return -EINVAL;
76 	return 0;
77 }
78 
79 static int mlxsw_sp_counter_sub_pools_prepare(struct mlxsw_sp *mlxsw_sp)
80 {
81 	struct mlxsw_sp_counter_sub_pool *sub_pool;
82 
83 	/* Prepare generic flow pool*/
84 	sub_pool = &mlxsw_sp_counter_sub_pools[MLXSW_SP_COUNTER_SUB_POOL_FLOW];
85 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, COUNTER_SIZE_PACKETS_BYTES))
86 		return -EIO;
87 	sub_pool->entry_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
88 						  COUNTER_SIZE_PACKETS_BYTES);
89 	/* Prepare erif pool*/
90 	sub_pool = &mlxsw_sp_counter_sub_pools[MLXSW_SP_COUNTER_SUB_POOL_RIF];
91 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, COUNTER_SIZE_ROUTER_BASIC))
92 		return -EIO;
93 	sub_pool->entry_size = MLXSW_CORE_RES_GET(mlxsw_sp->core,
94 						  COUNTER_SIZE_ROUTER_BASIC);
95 	return 0;
96 }
97 
98 int mlxsw_sp_counter_pool_init(struct mlxsw_sp *mlxsw_sp)
99 {
100 	struct mlxsw_sp_counter_sub_pool *sub_pool;
101 	struct mlxsw_sp_counter_pool *pool;
102 	unsigned int base_index;
103 	unsigned int map_size;
104 	int i;
105 	int err;
106 
107 	if (!MLXSW_CORE_RES_VALID(mlxsw_sp->core, COUNTER_POOL_SIZE))
108 		return -EIO;
109 
110 	err = mlxsw_sp_counter_pool_validate(mlxsw_sp);
111 	if (err)
112 		return err;
113 
114 	err = mlxsw_sp_counter_sub_pools_prepare(mlxsw_sp);
115 	if (err)
116 		return err;
117 
118 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
119 	if (!pool)
120 		return -ENOMEM;
121 
122 	pool->pool_size = MLXSW_CORE_RES_GET(mlxsw_sp->core, COUNTER_POOL_SIZE);
123 	map_size = BITS_TO_LONGS(pool->pool_size) * sizeof(unsigned long);
124 
125 	pool->usage = kzalloc(map_size, GFP_KERNEL);
126 	if (!pool->usage) {
127 		err = -ENOMEM;
128 		goto err_usage_alloc;
129 	}
130 
131 	pool->sub_pools = mlxsw_sp_counter_sub_pools;
132 	/* Allocation is based on bank count which should be
133 	 * specified for each sub pool statically.
134 	 */
135 	base_index = 0;
136 	for (i = 0; i < ARRAY_SIZE(mlxsw_sp_counter_sub_pools); i++) {
137 		sub_pool = &pool->sub_pools[i];
138 		sub_pool->size = sub_pool->bank_count *
139 				 MLXSW_SP_COUNTER_POOL_BANK_SIZE;
140 		sub_pool->base_index = base_index;
141 		base_index += sub_pool->size;
142 		/* The last bank can't be fully used */
143 		if (sub_pool->base_index + sub_pool->size > pool->pool_size)
144 			sub_pool->size = pool->pool_size - sub_pool->base_index;
145 	}
146 
147 	mlxsw_sp->counter_pool = pool;
148 	return 0;
149 
150 err_usage_alloc:
151 	kfree(pool);
152 	return err;
153 }
154 
155 void mlxsw_sp_counter_pool_fini(struct mlxsw_sp *mlxsw_sp)
156 {
157 	struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
158 
159 	WARN_ON(find_first_bit(pool->usage, pool->pool_size) !=
160 			       pool->pool_size);
161 	kfree(pool->usage);
162 	kfree(pool);
163 }
164 
165 int mlxsw_sp_counter_alloc(struct mlxsw_sp *mlxsw_sp,
166 			   enum mlxsw_sp_counter_sub_pool_id sub_pool_id,
167 			   unsigned int *p_counter_index)
168 {
169 	struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
170 	struct mlxsw_sp_counter_sub_pool *sub_pool;
171 	unsigned int entry_index;
172 	unsigned int stop_index;
173 	int i;
174 
175 	sub_pool = &mlxsw_sp_counter_sub_pools[sub_pool_id];
176 	stop_index = sub_pool->base_index + sub_pool->size;
177 	entry_index = sub_pool->base_index;
178 
179 	entry_index = find_next_zero_bit(pool->usage, stop_index, entry_index);
180 	if (entry_index == stop_index)
181 		return -ENOBUFS;
182 	/* The sub-pools can contain non-integer number of entries
183 	 * so we must check for overflow
184 	 */
185 	if (entry_index + sub_pool->entry_size > stop_index)
186 		return -ENOBUFS;
187 	for (i = 0; i < sub_pool->entry_size; i++)
188 		__set_bit(entry_index + i, pool->usage);
189 
190 	*p_counter_index = entry_index;
191 	return 0;
192 }
193 
194 void mlxsw_sp_counter_free(struct mlxsw_sp *mlxsw_sp,
195 			   enum mlxsw_sp_counter_sub_pool_id sub_pool_id,
196 			   unsigned int counter_index)
197 {
198 	struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
199 	struct mlxsw_sp_counter_sub_pool *sub_pool;
200 	int i;
201 
202 	if (WARN_ON(counter_index >= pool->pool_size))
203 		return;
204 	sub_pool = &mlxsw_sp_counter_sub_pools[sub_pool_id];
205 	for (i = 0; i < sub_pool->entry_size; i++)
206 		__clear_bit(counter_index + i, pool->usage);
207 }
208